Stem cellsNovember 2008
Marrow cell therapies for cardiovascular diseases.
The nascent field of regenerative medicine has taken root in cardiovascular disease. Preclinical data demonstrating hemangioblast potential of marrow cells and cardioprotective effects of growth factors served as the basis for numerous early phase clinical trials. With the first wave of safety and efficacy trials complete, much is still unknown regarding optimal cell dose and type, timing of injection, route of administration, mechanisms of action, and achievable response measures. The next generation of studies will aim to answers these questions and make way for cellular therapies that result in effective cardiac repair.
Exp Hematol. 2008 Jun;36(6):687-94
Induced pluripotent stem cells generated from patients with ALS can be differentiated into motor neurons.
The generation of pluripotent stem cells from an individual patient would enable the large-scale production of the cell types affected by that patient’s disease. These cells could in turn be used for disease modeling, drug discovery, and eventually autologous cell replacement therapies. Although recent studies have demonstrated the reprogramming of human fibroblasts to a pluripotent state, it remains unclear whether these induced pluripotent stem (iPS) cells can be produced directly from elderly patients with chronic disease. We have generated iPS cells from an 82-year-old woman diagnosed with a familial form of amyotrophic lateral sclerosis (ALS). These patient-specific iPS cells possess properties of embryonic stem cells and were successfully directed to differentiate into motor neurons, the cell type destroyed in ALS.
Science. 2008 Aug 29;321(5893):1218-21
Stem cell treatment in Amyotrophic Lateral Sclerosis.
Amyotrophic Lateral Sclerosis is a progressive fatal neurodegenerative disease that targets motor neurons. Its origin is unknown but a main role of reactive astrogliosis and microglia activation in the pathogenesis has been recently demonstrated. Surrounding neurons with healthy adjoining cells completely stops motor neuron death in some cases. Hence stem cell transplantation might represent a promising therapeutic strategy. In this study MSCs were isolated from bone marrow of 9 patients with definite ALS. Growth kinetics, immunophenotype, telomere length and karyotype were evaluated during in vitro expansion. No significant differences between donors or patients were observed. The patients received intraspinal injections of autologous MSCs at the thoracic level and monitored for 4 years. No significant acute or late side effects were evidenced. No modification of the spinal cord volume or other signs of abnormal cell proliferation were observed. Four patients show a significant slowing down of the linear decline of the forced vital capacity and of the ALS-FRS score. Our results seem to demonstrate that MSCs represent a good chance for stem cell cell-based therapy in ALS and that intraspinal injection of MSCs is safe also in the long term. A new phase 1 study is carried out to verify these data in a larger number of patients.
J Neurol Sci. 2008 Feb 15;265(1-2):78-83
In Vitro Generation of a Scaffold-Free Tissue-Engineered Construct (TEC) Derived from Human Synovial Mesenchymal Stem Cells: Biological and Mechanical Properties, and Further Chondrogenic Potential.
The purpose of this study was to characterize a tissue-engineered construct (TEC) generated with human synovial mesenchymal stem cells (MSCs). MSCs were cultured in medium with ascorbic acid 2-phosphate (Asc-2P) and were subsequently detached from the substratum. The detached cell/matrix complex spontaneously contracted to develop a basic TEC. The volume of the TEC assessed by varying initial cell density showed that it was proportional to initial cell densities up to 4 x 10(5) cells/cm(2). Assessment of the mechanical properties of TEC using a custom device showed that the load at failure and stiffness of the constructs significantly increased with time of culture in the presence of Asc-2P, while in the absence of
Asc-2P, the constructs were mechanically weak. Thus, the basic TEC possesses sufficiently self-supporting mechanical properties in spite of not containing artificial scaffolding. TEC further cultured in chondrogenic media exhibited positive alcian blue staining with elevated expression of chondrogenic marker genes. Based on these findings, such human TEC may be a promising method to promote cartilage repair for future clinical application.
Tissue Eng Part A. 2008 Jul 17
Chondrogenesis from immortalized human mesenchymal stem cells: comparison between collagen gel and pellet culture methods.
Human mesenchymal stem cells (hMSCs) can differentiate into cells of connective tissue lineages, including cartilage. To overcome the limiting autogenous chondrocyte populations available in cartilage repair, various methods have been developed to maximize chondrogenesis of hMSCs in vitro, most of which use cells derived from primary culture. In this study, we compared chondrogenesis of immortalized hMSCs embedded in collagen gel to those grown in pellet culture. The hMSCs in collagen scaffolds expressed more glycosaminoglycan than those in pellet culture. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) analysis demonstrated that the expression of genes encoding sox-9, aggrecan, and types I and II collagen increased in pellet culture over time. However, in the collagen cultures, only type II collagen and aggrecan expression increased over time, whereas sox-9 expression remained unchanged and type I collagen expression decreased. These results indicate that the immortalized hMSC line is a promising tool for further in vitro chondrogenic studies.
Artif Organs. 2008 Jul;32(7):561-6
Stem-cell based therapies for brain tumors.
Advances in understanding neural stem cell (NSC) biology have facilitated the development of novel cell-based therapies for brain malignancies. NSCs are the most immature progenitor cells in the nervous system that have the ability to self-renew, differentiate into terminal neural cell types, and extensively migrate to areas of pathology in the central nervous system. Because of their inherent tumor-trophic properties and their capacity to differentiate into all neural phenotypes, NSCs represent a powerful tool for the treatment of both diffuse and localized neurological disorders. Progress has validated the feasibility of using engineered NSCs as cell-based therapeutic agents to eliminate malignant cells in the brain. This review discusses the therapeutic potential of NSCs focusing on brain tumors.
Curr Opin Mol Ther. 2008 Aug;10(4):334-42
Disease-Specific Induced Pluripotent Stem Cells.
Tissue culture of immortal cell strains from diseased patients is an invaluable resource for medical research but is largely limited to tumor cell lines or transformed derivatives of native tissues. Here we describe the generation of induced pluripotent stem (iPS) cells from patients with a variety of genetic diseases with either Mendelian or complex inheritance; these diseases include adenosine deaminase deficiency-related severe combined immunodeficiency (ADA-SCID), Shwachman-Bodian-Diamond syndrome (SBDS), Gaucher disease (GD) type III, Duchenne (DMD) and Becker muscular dystrophy (BMD), Parkinson disease (PD), Huntington disease (HD), juvenile-onset, type 1 diabetes mellitus (JDM), Down syndrome (DS)/trisomy 21, and the carrier state of Lesch-Nyhan syndrome. Such disease-specific stem cells offer an unprecedented opportunity to recapitulate both normal and pathologic human tissue formation in vitro, thereby enabling disease investigation and drug development.
Cell. 2008 Sep 5;134(5):877-86
The problem of deception in embryonic stem cell research.
The field of embryonic stem cell research has been plagued by exaggeration and misrepresentation, as three major journals have had to retract significant claims about progress in this field. This problem is exacerbated by the politicized climate in which the research is conducted and defended; it may also lie deeper, in a utilitarian ethic that in principle could justify unethical actions for admittedly worthwhile long-term goals. Such an ethic risks undermining the credibility of science, which must show a commitment to the facts that is independent of social and political goals.
Cell Prolif. 2008 Feb;41 Suppl 1:65-70
Stem cell research: cloning, therapy and scientific fraud.
Stem cell research has generated intense excitement, awareness, and debate. Events in the 2005-2006 saw the rise and fall of a South Korean scientist who had claimed to be the first to clone a human embryonic stem cell line. From celebration of the potential use of stem cells in the treatment of human disease to disciplinary action taken against the disgraced scientists, the drama has unfolded throughout the world media. Prompted by an image of therapeutic cloning presented on a South Korean stamp, a brief review of stem cell research and the events of the Woo-suk Hwang scandal are discussed.
Clin Genet. 2006 Oct;70(4):302-5
Human cloning and stem cell research: engaging in the political process. (Legislation review: prohibition of Human Cloning Act 2002 and the research involving Human Embryos Act).
Committees appointed by governments to inquire into specific policy issues often have no further role when the Committee’s report is delivered to government, but that is not always so. This paper describes the activities of members of the Australian Committee on human cloning and embryo research (the Lockhart Committee) to inform Parliament and the community about the Committee’s recommendations after its report was tabled in Parliament. It explains their participation in the political process as their recommendations were debated and amending legislation was passed by Parliament. It illustrates a method of communication about scientific and policy issues that explores people’s concerns and what they ‘need to know’ to make a judgment; and then responds to questions they raise, with the aim of facilitating discussion, not arguing for one view. The paper considers whether this type of engagement and communication is appropriate and could be used in other policy discussions.
Med Law. 2008 Mar;27(1):119-30